Supporters call the borrowing an investment in the future, contributing to a strong business climate and relieving air pollution in some metropolitan areas. Critics, concerned that almost $1 billion of the roughly $8 billion annual TxDOT budget goes to debt service, question how long taxpayers can afford to borrow to keep up with road building.

The story says legislators have resorted to presenting propositions to voters rather than voting themselves to raise gas taxes and increase vehicle registration fees. Rep. Joe Pickett, D-El Paso, former chairman of the House Transportation Committee, worries that counties and cities reimbursed now with borrowed money are going to have to shoulder more of the cost of their highway expansion and upkeep.

"We've advanced as much as we can with the ability to borrow funds," Jodi Hodges, a spokeswoman for the department, said. "Now we're having to pay it back with interest."